Viewing device for use with coded data on a surface

ABSTRACT

A viewing device is used with coded data on a surface. The device includes a sensor arrangement for sensing the coded data when the device is placed on the surface, and a processor in signal communication with the sensor arrangement. The processor is configured to decode the coded data. Also included is a transceiver for transmitting the decoded data to a computer system, and to subsequently receive a file pre-associated with the decoded data from the computer system. The device also includes a display configured to display the received file to a user.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a Continuation Application of U.S. application Ser. No.11/281,671 filed on Nov. 18, 2005, which is a Continuation Applicationof U.S. application Ser. No. 10/943,843, filed on Sep. 20, 2004, nowissued U.S. Pat. No. 7,019,319, which is a Continuation of U.S.application Ser. No. 09/722,147, filed on Nov. 25, 2000, now issued asU.S. Pat. No. 6,946,672 all of which is herein incorporated byreference.

FIELD OF INVENTION

The present invention relates generally to devices for interacting withcomputer systems, and in particular, to a device which may be used torender otherwise passive surfaces audiovisually interactive viainvisible surface codings.

CO-PENDING APPLICATIONS

Various methods, systems and apparatus relating to the present inventionare disclosed in the following co-pending applications filed by theapplicant or assignee of the present invention simultaneously with thepresent invention:

6,530,339 6,631,897 7,295,839 09/722,174 7,175,079 7,064,851 6,826,5476,741,871 6,927,871 6,980,306 6,965,439 6,788,982 7,263,270 6,788,2936,946,672 7,091,960 6,792,165 7,105,753 7,182,247

The disclosures of these co-pending applications are incorporated hereinby cross-reference.

Various methods, systems and apparatus relating to the present inventionare disclosed in the following co-pending applications filed by theapplicant or assignee of the present invention on Oct. 20, 2000:

7,190,474 7,110,126 6,813,558 6,965,454 6,847,883 7,131,058 09/693,6906,982,798 6,474,888 6,627,870 6,724,374 7,369,265 6,454,482 6,808,3306,527,365 6,474,773 6,550,997The disclosures of these co-pending applications are incorporated hereinby reference.

Various methods, systems and apparatus relating to the present inventionare disclosed in the following co-pending applications filed by theapplicant or assignee of the present invention on 15 Sep. 2000:

6,679,420 6,963,845 6,995,859 6,720,985The disclosures of these co-pending applications are incorporated hereinby reference.

Various methods, systems and apparatus relating to the present inventionare disclosed in the following co-pending applications filed by theapplicant or assignee of the present invention on Jun. 30, 2000:

6,824,044 6,678,499 6,976,220 6,976,035 6,766,942 7,286,113 6,922,7796,978,019 09/607,843 6,959,298 6,973,450 7,150,404 6,965,882 7,233,9247,007,851 6,957,921 6,457,883 6,831,682 6,977,751 6,398,332 6,394,5736,622,923The disclosures of these co-pending applications are incorporated hereinby cross-reference.

Various methods, systems and apparatus relating to the present inventionare disclosed in the following co-pending applications filed by theapplicant or assignee of the present invention on 23 May 2000:

6,428,133 6,526,658 6,315,399 6,338,548 6,540,319 6,328,4316,328,425 6,991,320 6,383,833 6,464,332 6,390,591 7,018,0166,328,417 09/575,197 7,079,712 6,825,945 7,330,974 6,813,0396,987,506 7,038,797 6,980,318 6,816,274 7,102,772 7,350,2366,681,045 6,728,000 7,173,722 7,088,459 09/575,181 7,068,3827,062,651 6,789,194 6,789,191 6,644,642 6,502,614 6,622,9996,669,385 6,549,935 6,987,573 6,727,996 6,591,884 6,439,7066,760,119 7,295,332 6,290,349 6,428,155 6,785,016 6,870,9666,822,639 6,737,591 7,055,739 7,233,320 6,830,196 6,832,7176,957,768 09/575,172 7,170,499 7,106,888 7,123,239 6,409,3236,281,912 6,604,810 6,318,920 6,488,422 6,795,215 7,154,638 6,859,289The disclosures of these co-pending applications are incorporated hereinby cross-reference.

BACKGROUND

Devices such as personal computers, personal digital assistants and evenmobile phones may be used to interact with audiovisual information andwith computer applications which have an audiovisual interface.

In general, these devices don't provide access to situated interactiveinformation or application interfaces, e.g. to an online fan club chatgroup associated with a concert poster encountered at a train station,or a mortgage calculator associated with a flyer received through themail. Each device must be used to seek out the desired information orapplication interface through a virtual space accessible through thedevice, or the information or application must be brought to the devicein a device-compatible physical format.

The present invention utilizes methods, systems and devices related to asystem referred to as “netpage”, described in our co-pendingapplications listed above, wherein invisible coded data is disposed onvarious surfaces to render the surfaces interactive in the manner ofgraphical user interfaces to computer systems.

SUMMARY OF INVENTION

In one broad form the invention provides a hand held viewing device withone or more sensors capable of sensing coded data. Images which includecoded data are sensed by the viewer and decoded. The decoded informationis transmitted to a computer system which associates the decoded datawith one or more files stored on the system, using previously storedassociation data. The file or files are transmitted to the viewer and tothe user via the viewer's display screen.

Accordingly, in one broad form, the invention provides a viewer for thedownload at least one file and the display of visual information basedon the at least one file, the viewer including:

at least one sensor for sensing coded data on or in a substrate and forgenerating first data;

a transceiver for transmitting said first data or second data at leastpartially based on the first data to a computer system and for receivingat least one file associated with an identity derived from the firstdata from the computer system;

at least one display device for outputting visual information based atleast partially on said at least one file.

The viewer may include a decoder for receiving said first data from thesensor device and for outputting said second data to the transceiver;

The visual information may include text or images or both. Images may bestill or moving images. Audio information may also be output by thedevice.

Where the display of the viewer overlays part or all of the substratethe visual information may include a component which substantiallycorresponds to the visual appearance of the part of the substrateoverlain by the display, including any markings on the substrate visibleto the average unaided human eye. The component may be aligned withmarkings on the substrate visible to the average unaided human eye or itmay be aligned with the viewer. The component may be modified as theposition of the viewer on the substrate changes, or under user control.The component may correspond to an area of the substrate larger orsmaller than the area of the display.

After receiving one or more files, the viewer may sequentially displaysall visual information based on the file(s).

The viewer may display first visual information corresponding to uncodedvisible text or markings on the substrate and second visual informationcorresponding to coded visible text or blank areas on the substrate, soas to enable an authorized viewer or user to view secure or confidentialinformation which is not available for view on the substrate.

In use the viewer may be moved across a substrate tiled with dataencoded tags and the output is modified as the viewer is moved acrossthe substrate so as to correspond to the interface on the substrate.

The visual output may correspond to the interface but be text in thesame or a different language as the interface. The visual output mayinclude the same, more or less information as the interface on thesubstrate. The interface may represent information, such as bank accountinformation which is not displayed on the interface in full but isdisplayed in full via the viewer.

The device preferably has controls to enable the optical output todisplay information with a size the same, less than or more than thecorresponding information on the interface.

The device preferably includes a touch sensitive overlay and the opticaloutput includes interactive elements by which the user may modify theoptical output by interaction with the touch screen.

The device may also display motion pictures, in which case the physicalrelationship between the viewer and the substrate once the coded datahas been sensed and transmitted may be immaterial.

The viewer may also include memory into which a file or files, aredownloaded for subsequent viewing.

When the viewer is lifted from the page the portion of the page withwhich the viewer was last in contact can be retained by the viewer andremain interactive. The viewer can do this by default, or alternativelyonly when the user ‘freezes’ or ‘snaps’ the current view before liftingthe viewer from the page, as discussed in more detail below. The viewermay include controls for rotating and panning the view after the viewerhas been lifted from the page, allowing the viewer to be used tonavigate an entire page after only a single contact with it. Thenavigation controls may be in the form of a small joystick, or a pair oforthogonal thumb wheels, or may be provided via the touch-screen.

The viewer preferably senses the identity of the underlying page as wellas its own position and orientation relative to the page using a netpagesensor embedded in the viewer. The viewer can contain multiple sensors(one in each corner, for example), so that it works when only partiallyoverlapping a page or even when overlapping multiple pages. A singlesensor located in the center of the viewer is sufficient for mostpurposes, however, and is most economical.

The viewer is capable of providing an enhanced view of the underlyingpage. In the dark, for example, it can provide a lit view of the page.When magnification is needed, it can provide a zoomed view of the pagevia its zoom controls. The viewer may also be able to provide azoomed-out view of the page.

The viewer can provide an alternative (or additional) netpage data entrymechanism, i.e. the usual kinds of inputs, including drawing andhandwriting and gestures, can be captured relative to the displayed pagevia the touch-screen instead of relative to the physical page via thenetpage pen.

The viewer can provide access to dynamic content, such as audio andvideo, in the context of a physical page. Playback controls whichprovide access to interactive content are typically only shown when thepage is viewed through the viewer. They may be shown on the printed pageas well, although ideally in a form which clearly indicates that theyare inactive. Status information such as playing time may also be shownon-screen. The underlying page layout should provide space for thedisplay of interactive controls and status information, so that theprinted page and on-screen display remain compatible. Interactivecontrol is not limited to playback of streaming media such as audio andvideo. It can include arbitrary interaction with a computer application.It may, for example, include manipulation of an object in 3D.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view from above of an embodiment of theinvention;

FIG. 2 is a perspective view from below of the FIG. 1 device;

FIG. 3 is an exploded perspective view from above of the FIG. 1 device;

FIG. 4 is a side view from the rear of the device of FIG. 1;

FIG. 5 is a plan view from above of the FIG. 1 device;

FIG. 6 is a side view from the right of the FIG. 1 device;

FIG. 7 is a cross-sectional view taken along line AA of FIG. 5;

FIG. 8 is a perspective view from above of the internal components ofthe FIG. 1 device;

FIG. 9 is a perspective view from below of the internal components ofthe FIG. 1 device;

FIG. 10 is an exploded perspective view of the underside of the PCB ofthe FIG. 1 device;

FIG. 11 is a plan view showing the FIG. 1 device in use on a codedsubstrate in a first orientation;

FIG. 12 is a view from the side of the FIG. 11 arrangement;

FIG. 13 is a plan view of the FIG. 1 device in a second orientation onthe substrate of FIG. 11.

FIG. 14 is a plan view of the FIG. 1 device viewer showing a “lifted”view of a page;

FIG. 15 is a plan view of the FIG. 1 device showing a view of a page indarkness;

FIG. 16 is a plan view of the FIG. 1 device showing a “zoomed-in” viewof a page;

FIG. 17 is a plan view of the FIG. 1 device showing a “zoomed-out” viewof a page;

FIG. 18 is an example of a movie library page;

FIG. 19 is a plan view of a viewer showing a view of a playable videoclip;

FIG. 20 is a plan view of a viewer showing a snapped and lifted view ofa playable video clip;

FIG. 21 shows an example of a music library page;

FIG. 22 shows a plan view of a viewer showing a view of playable musicclip;

FIG. 23 shows a plan view of a viewer showing a snapped and lifted viewof a playing audio clip;

FIG. 24 shows an example of PIN advice letter from bank;

FIG. 25 shows a viewer showing a secure view of personal data;

FIG. 26 shows an example of “fill-in” form;

FIG. 27 shows a viewer allowing form fill-in by a user;

FIG. 28 shows a schematic of viewer's electronic components;

FIG. 29 shows a document element view; and

FIG. 30 shows the viewer interaction with a netpage network

DETAILED DESCRIPTION OF PREFERRED AND OTHER EMBODIMENTS

Referring to FIGS. 1 to 10, there is shown a viewer 100. The viewer hasa color LCD screen 102, control buttons 186, 192 & 194, a speaker 106,volume control 108, an audio out jack 110 and a infrared sensing device1 12. The LCD screen 102 has a touch sensitive overlay 132.

The viewer 100 is a netpage system enabled device and communicates witha netpage system in a similar manner to that disclosed in the co-pendingapplications referred to earlier and in particular to applications U.S.Ser. No. 09/722,142 and U.S. Ser. No. 09/721,893.

The viewer 100 has upper and lower moldings 114 and 116 respectivelywhich encapsulate a PCB 118 and all of the electronic components aremounted on or connected to this PCB. Power for the device is supplied bya rechargeable 3 volt lithium ion battery 120. The battery is not userreplaceable and is located within the casing.

The two moldings 114 and 116 clip together at the upper edge 122 and areheld together by three screws 124 extending through apertures 126 in thelower molding to engage in threaded studs (not shown) in the uppermolding 114. The screws pass through holes 128 in the PCB and sandwichthe PCB between the lower bosses 130 and the studs in the upper molding.

The PCB includes four electrical switches which are acted on by the pushbuttons. The zoom buttons 186 allows the view to be zoomed in, zoomedout, and, when activated simultaneously, to be reset to normal scale.The snap button allows the nearest dynamic or interactive object to besnapped to the screen. It more generally allows the current view to bede-synchronized (or ‘frozen’ or ‘lifted’) from the underlying page.Optional pan controls allow the view to be panned independently of theunderlying page. The power button allows the viewer to be switched onand off. The volume control, in the form of a potentiometer, allows thevolume of the viewer's audio output to be controlled. The audio outputis used to play audio content associated with a page, and optionally toprovide operating feedback to the user.

A combined data and power connector 134 is connected to the PCB and isaccessible via opening 136 in the casing. The connector 134 includes apower input socket 138 for recharging of the battery 120 and a datasocket 140 for input/output of data to and from the device. Theconnector 134 is connected to the PCB via a flexible PCB 142 andconnectors 144 and 146.

The speaker 106 is also connected to the PCB at its lower edge viaconnector 148 and is positioned between the PCB and the lower edge ofthe casing. The speaker may be hard wired to the PCB rather than beingprovided with a removable connector.

Digital audio generated by the viewer is converted to analog via adigital-to-analog converter (DAC) 173, is amplified by an amplifier 177subject to the volume control 108, and is output to a speaker 106 or toan external audio device via an audio out jack 11O. The speaker isdisabled when the audio out jack 110 is in use.

The volume control 108 and audio out jack 110 are mounted directly onthe left hand side of the PCB and are accessible via openings 154 and156 respectively in the left hand side of the casing.

The battery 120 is also positioned between the PCB and the lower edge ofthe casing. A removable connector 150 is provided to connect the batteryto the PCB. However, since the battery is not intended to be userreplaceable, a permanent connection may be used. The battery ispreferably shaped to fit the casing and accordingly has a beveled corner152.

Mounted on the lower surface of the PCB is the optical sensor device 112capable of detecting infrared markings on a substrate. The sensingdevice 112 comprises an infrared LED 160 and an image sensor 162. In useinfrared light is emitted from the LED 160 and passed through an opticalguide 164 and then through an aperture 166 in the lower molding.Reflected light passes through the aperture 166, the optical molding 164and is focused onto the CCD 162. The optical molding preferably includesa lens 168 and may include a beam splitter/combiner to allow light fromand to the LED and the CCD to follow the same path. The LED 160 may bestrobed in synchrony with image capture to prevent motion-blurring ofcaptured tag images. The image sensor 162 typically consists of a200×200 pixel CCD or CMOS image sensor with a near-infrared bandpassfilter.

The PCB also includes a processor chip 170, DRAM 172, flash ROM 174,display controller 250 for controlling the LCD, a transceiver chip 178and an aerial 180.

In order to display video, the color display 102 usefully has a 4:3aspect ratio, although with the advent of DVD and digital broadcasting,digital video content with wide screen aspect ratios of 16:9 and widerare becoming more prevalent. The aspect ratio used is not critical. Theminimum useful resolution is preferably SIF resolution, which has asquare-pixel equivalent of 320×240 pixels. In order to display text, thedisplay preferably has a pitch of at least 100 pixels per inch, giving amaximum diagonal display size of four inches. Larger displays withcorrespondingly more pixels provide obvious benefits, although with theadded expense of a larger form factor and greater processing andcommunications bandwidth requirements.

The display ideally mimics the optical properties of the underlyingpaper, i.e. the paper's high reflectivity, high contrast, and Lambertianreflectance function. Although the display may be a conventionalback-lit color LCD, such as an active-matrix twisted-nematic (TN) colorLCD, it is more usefully a reflective display, such as a passive-matrixcholesteric color LCD from Kent Displays Inc., an electrophoreticdisplay from E Ink Corporation, or a rotating ball display from XeroxCorporation, Inc. The display may also be a low cost organic LED (OLED)display.

Display output generated by the viewer is routed to the display 102 viathe display controller 250. Assuming a 320×240 RGB pixel display, thedisplay controller 250 has an associated or embedded 0.25 Mbytesingle-buffered or 0.5 Mbyte double-buffered display memory 181.

A dedicated compressed video and audio decoder 171 which producessquare-pixel progressive-scan digital video and digital audio output isalso provided. To handle MPEG-1 encoded video and audio, a video andaudio decoder similar to a C-Cube CL680 decoder may be used. To handleMPEG-2 encoded video and audio, a video and audio decoder similar toC-Cube's ZiVA-3 decoder may be used. An MPEG-1 decoder typically uses a4 Mbit DRAM during decoding, while an MPEG-2 decoder typically uses a 16Mbit SRAM during decoding. The decoder memory 179 may be dedicated tothe decoder, or may be part of a memory 172 shared with the processor.

The processor unit 175 controls and coordinates the various electroniccomponents of the viewer. The processor executes software whichmonitors, via the sensor(s) 112, the identity of the underlying page andthe position of the viewer relative to the page; communicates theidentity and position data to a netpage base station via the wirelesstransceiver 178; receives identity- and position-related page data fromthe base station via the transceiver; renders user output to the colordisplay 102 and audio output; and interprets user input captured via theuser interface buttons 104 and the screen's touch sensor 132. Theembedded software executed by the processor is stored in thenon-volatile memory 174, which is typically a ROM and/or flash memory.Identity information unique to the viewer, as well as communicationsencryption keys, are also stored in non-volatile memory. Duringexecution the processor utilizes faster volatile memory, typically inthe form of a 256 Mbit (32 Mbyte) dynamic RAM (DRAM) 172.

The processor unit 175 communicates with the other components via ashared bus 183. The processor 175, the bus 183, and any number of othercomponents may be integrated into a single chip. As indicated in FIG. 28the integrated components may include the digital transceiver controller183, the video decoder interface 187 and the tag image sensor interface185. If a fingerprint sensor 189 is provided a fingerprint sensorinterface 191 may be incorporated in the integrated components. In amore highly integrated chip, the integrated components may also includethe display controller 250, the image sensor 112, the compressed videoand audio decoder 171, the audio digital-to-analog converter (DAC) 173and the memory 172. The analog radio transceiver 178 is unlikely to beintegrated in the same chip, but may be integrated in the same package.A parallel interface 193 links the buttons 104, touch sensor 132 and theLED 160 to the bus 183.

The processor 170 is sufficiently powerful to render page content atinteractive rates, i.e. at least 10 Hz, and to transform videodecompressed by the video decoder and merge it with other page content.If it is sufficiently powerful, then it may also perform video and audiodecoding, obviating the need for a video and audio decoder.

The transceiver 178 is typically a short-range radio transceiver. It maysupport any of a number of wireless transmission standards, includingBluetooth/IEEE 802.15, IEEE 802.11, HomeRF/SWAP, HIPERLAN, and OpenAir.Bluetooth/IEEE 802.15, IEEE 802.11-1997, HIPERLAN, OpenAir, andHomeRF/SWAP all support transmission rates in the range of 1 to 2Mbit/s. IEEE 802.11b supports transmission rates of 5.5 Mbit/s and 11Mbit/s. HIPERLAN also supports a transmission rate of 24 Mbit/s in analternative mode. Beyond these currently-supported wireless LAN (WLAN)standards, next-generation WLAN standards promise to supporttransmission rates of 100 Mbit/s and higher.

The viewer may alternatively be connected to the base station by cable,or may utilize a non-radio-frequency wireless transport, such asinfrared. IEEE 802.11, for example, optionally utilizes an infraredtransport. IrDA also utilizes an infrared transport.

The lower surface of the lower casing 16 is provided with four outerfeet 182 and four inner feet 184. The outer feet are located near thecorners of the device whilst the inner feet 184 are located at thecorners of a square centered on the lens 168.

All eight feet extend the same distance and enable the device to beplaced on a planar surface with a small gap between the surface and thegeneral plane of the lower molding. The feet have a rounded contactsurface and this aids in sliding the device across the surface. Theinner feet 184 ensure that if one or more of the outer feet 182 are notsupported the device does not tip relative to the surface. They also aidin keeping the surface flat near the sensing device 112.

The sensor device 112 is infrared sensitive. The image sensor 162 issensitive to infrared light, either inherently or by use of filters andthe LED 160 emits infrared light, again inherently or by use of filters.The lens 168 is focused on the plane of the inner and outer feet 182 and184, as this is where a substrate to be sensed will be located. Thesensor device is capable of detecting infrared absorptive tags, such asnetpage tags. For a full description of the processes involved,reference is made to co-pending application U.S. Ser. No. 09/721,893referred to earlier. The CCD 162, the LED 160 and processing functionsincorporated in the processor chip 170 are similar to those disclosed inthe co-pending application.

The device is thus capable of sensing and decoding netpage tags on asubstrate. Image data captured by the CCD 162 is sent to the processor175 and decoded to a region ID (or page ID) and tag ID. The region IDand tag ID, together with other necessary information, is transmitted tothe netpage system via the transceiver chip 178 and aerial 180. Thenetpage system resolves the region ID and tag ID to correspondingdocument data which it transmits back to the device. The processor 180receives the data via the aerial 180 and transceiver. The processorrenders the data for display on the color display 102 via the displaycontroller 250.

The LCD screen 102 is overlaid with a touch sensitive overlay 132. Whenviewing information via the LCD screen, the screen will include controlsto enable the user to control the device by touching the screen with astylus.

Usage

Referring to FIGS. 11 and 12, in use the device 100 is placed on asubstrate 200 having netpage tags 202 tiled over its surface. Thesubstrate 200 may be paper, electronic paper such as used by E InkCorporation, a plastic sheet or any other suitable substrate. As seen inFIG. 12 the sensor device 112 senses one or more of the tags 202,decodes the coded information and transmits this decoded information tothe netpage system. In FIG. 11 the substrate carries human discemabletext or other markings 204 and so is readable without the device 100.

The device may be used with a surface which only carries netpage tagsand so appears as a blank document to a user without an authorizedviewer. As discussed in our earlier applications, each tag incorporatesdata which identifies the page it is on and its location within thepage. The netpage system is thus capable of determining the location ofthe viewer 100 and so can extract information corresponding to thatposition. When displaying static images or text the displayedinformation usually corresponds to the human discernable text or othermarkings 204 on the substrate. Additionally the tags include informationwhich enables the device and/or system to derive an orientation of thedevice relative to the page from the tags. This enables the informationdisplayed to be rotated relative to the device to match the orientationof the text 204. Thus information 206 displayed by the viewer appears tobe what is on the page in the corresponding position under the viewer.

When the viewer first comes into contact with a new page, it downloadsthe corresponding page description from the relevant netpage pageserver. It then renders the viewer's view according to the current viewtransform, i.e. according to the viewer's current zoom setting and itsposition and rotation relative to the underlying page. Whenever the viewtransform changes, i.e. because the user moves the viewer or changes theviewer's zoom setting, the viewer re-renders the view according to thenew view transform. For the purposes of the following discussion, thesize of the viewer's window onto the page is also assumed to be part ofthe view transform.

Whenever the view transform changes, the viewer transmits the viewtransform to the netpage page server responsible for the underlyingpage. This allows the page server to commence streaming dynamic objectswhich have come into view and to cease streaming dynamic objects whichare no longer in view. It also allows the page server to provide theviewer with static objects, such as images, at a suitable resolution.

As the device is moved the sensor device 112 images the same ordifferent tags, which enables the device 100 and/or system to update thedevice's relative position on the page and to scroll the LCD display asthe device moves. The position of the viewer relative to the page caneasily be determined from the image of a single tag; as the viewer movesthe image of the tag changes and from this change in image the positionrelative to the tag can be determined. The system “knows” the absoluteposition of the tag on the page from its tag ID and so the absoluteposition of the viewer on the page may be derived. The viewer sensestags, and thereby its time-varying position relative to the substrate,and sufficiently frequently that movement of the viewer results in asmooth, as opposed to a jerky, scrolling of the display.

The information 206 displayed in the viewer is preferably aligned withthe markings 204 on the page 200, so that it appears as if the viewer100 is transparent. Thus the orientation of the viewer 100 does notalter the orientation of the displayed information 206, as seen in FIG.13.

However, as seen in FIG. 14, the text 206 displayed on the LCD screen102 need not remain aligned with the markings 204 on the page 200 butmay remain aligned with the viewer 100. The user may use the ‘snap’button 192 to instruct the viewer to display information aligned withthe viewer, not the page text 204.

The viewer 100, if provided with backlighting of the LCD 132, is capableof displaying information in the dark. FIG. 15 shows a page 200 with aviewer 100 displaying information 206 corresponding to information onthe page which is not visible due to lack of ambient light.

Whilst the information 206 shown on the LCD 102 is similar to theprinted information 204, it need not be identical. The left hand controlbutton 186 is a rocker type device. When pressed on the left, the buttonactivates switch 188 and when pushed on the right the button activatesswitch 190. Pushing down centrally or equally on the left and rightactivates both switches 188 and 190. Pressing on the left switch 186causes the display to zoom in whilst pressing on the right causes thedisplay to zoom out. Pressing centrally resets the display to the devicedefault, which may be a 1 to 1 ratio compared to the text 204. FIG. 16shows a viewer 100 displaying “zoomed-in” text 206 whilst FIG. 17 shows“zoomed-out” text 206, both being of text 204 on a page 200.

The device is not limited to simply reproducing the text printed on apage. Because the printed text is associated with one or more electronicdocuments in the netpage system, the device can provide more than justthe text to the user. Where a document has references, such as footnotesor hyperlinks, these references may be shown on screen. The user maythen view those references by touching the reference on screen. This ispicked up by the touch sensitive overlay 132 and the appropriateinformation displayed, either in a new window or as an overlay on theexisting text. This information may be displayed for a set period, afterwhich the display reverts to its original display. The system may alsocause additional information to be shown on the LCD screenautomatically. Where the page is mainly text the device 100 may be setto a read mode whereby as the user reads the page the text is recitedand output via speaker 106. This would be of benefit to people learningto read, such as children or those learning a foreign language. Using astylus and the touch sensitive overlay the user indicates where they arereading and the corresponding text is spoken by the machine.Pronunciation of a word or phrase may be practiced by repeatedly drawingthe stylus over the relevant text.

The text displayed need not be in the same language or script as thetext on the paper. The device may be set to display a single language,when possible. Thus if a netpage document exists in both English andItalian, for example, the device could be set to display the Italiantext even though the printed document is in English. Where a documentonly exists in one language, the system may be configured to eitherdisplay the document in that language or nothing except a message to theeffect that document is not available in the desired language.

If desired the device may be set to an “automatic recital” mode in whichthe screen automatically scrolls through the entire document, with orwithout a corresponding aural recital. An aural recital may also occurwithout a corresponding display of text. The speed of playback may becontrolled by the user. Since each tag 202 on the page identifies thedocument the device merely needs to sense one tag on the page for thosefeatures to be activated.

Depending on the document size and device memory, an entire document maybe downloaded to the device or “chunks” of data may be downloaded asrequired or as expected to be required. A simple text document, even ofmany pages, is relatively small and may be buffered in its entiretywithout needing extra memory; the device is capable of playing video, aswill be discussed later, and the buffer needed to accommodate variationsin data reception for video display is more than sufficient toaccommodate most text documents. Where an entire document is downloaded,preferably the download is configured to initially send datacorresponding to the location of the viewer on the page.

When viewing text or static images the device may have two modes. Thefirst mode, described above, maintains a correlation between theinformation displayed on the LCD screen and the position of the deviceto the substrate. In the second mode, the device may be moved withoutaffecting the display; the scrolling and autoplay feature discussedabove being a subject of this feature. To set the device to the secondmode the user may press the ‘snap’ button 192. Once in the second modemovement of the device across the paper does not automatically affectthe information displayed. The information displayed continues tocorrespond to the location when the viewer was placed in this mode.Movement of information across the display in this mode is controlled bythe user. A document will continue to be displayed or be accessibleuntil the device is placed on a different netpage encoded substrate, atwhich point the device may normally revert to its first mode.Alternatively, the user must explicitly revert to the first mode bypressing the ‘snap’ button again.

FIGS. 18, 19 and 20 provide an example of the interaction of the viewerwith a video clip. FIG. 18 shows a sample ‘movie library’ page 210containing multiple video clip icons 212. Again the page is tiled withnetpage tags, not shown. FIG. 19 shows the view the viewer provides of avideo clip icon, which includes playback controls 214, which may beactivated via the viewer's touch-screen, and the playing time. Thescreen-displayed information 214, 216 remains fixed relative to thedisplayed text 218 as the viewer moves. FIG. 20 shows the view theviewer shows once the nearest video clip is ‘snapped’ to the screen,i.e. with the video clip filling the screen, ready to be played. Asseen, all of the playback controls and playing time are displayed whenthe view is snapped. The user snaps the nearest interactive or dynamicobject to the centre of the screen by pressing the viewer's snap button.Alternatively or additionally, an interactive object may snap to thescreen automatically when activated, e.g. when played in the case of avideo clip. In the example, status information and controls aresuperimposed on the video clip to maximize the video clip's use of thescreen. The viewer 100 typically suppresses the display of the statusinformation 216 and playback controls 214 once the clip is playing,either until the clip terminates or until the user initiates furtherinteraction by touching the touch-screen 132. The playing time ispreferably displayed in units of hours, minutes and seconds, and ispreceded by a current chapter number if the clip has multiple chapters.The playback controls 214 include stop, play, pause, skip backwards andskip forwards. When the clip is stopped or paused, a play button isshown. When the clip is playing, a pause button is shown in place of theplay button. The skip controls skip to the start/end of the currentchapter, or, if already at the start/end, to the start of theprevious/next chapter. If held, rather than pressed momentarily, theskip controls scan backwards/forwards through the clip, i.e. they playthe clip at a greater than normal rate backwards/forwards.

As an alternative to on-screen controls, the viewer may providededicated playback control buttons which control whichever dynamicobject is current. It may also provide a dedicated display, such as amonochrome segment LCD, for the display of chapter (or track)information and playing time.

The viewer streams dynamic objects such as video clips from any numberof servers via the current netpage base station. The viewer is optimizedto only stream objects which are currently visible on the viewer'sscreen. When an object ceases to be displayed, it may be configured toautomatically pause, or it may continue to ‘play’ on the server, withoutconsuming communications bandwidth, so that when it is once againdisplayed its playback has progressed in time as expected by the user.

FIGS. 21, 22 and 23 provide an example of the interaction of the viewer100 with an audio clip. FIG. 21 shows a sample ‘music library’ page 220containing multiple audio clip entries 224. The entries may be groupedunder a title 222. FIG. 22 shows the view the viewer provides of a setof audio clip entries 224, which includes an indication of a ‘current’audio clip entry with an associated play button 226 which may beactivated via the viewer's touch-screen. The current entry is preferablysimply the entry closest to the center of the screen and so changes asthe viewer is moved, unless a clip is playing. If no entry issufficiently close, then no entry is current. FIG. 23 shows the view theviewer provides once the nearest audio clip is snapped to the screen orselected, i.e. with clip-related information filling the screen. Notethat, as illustrated in the example, a snapped view can be quitedifferent from any view directly derivable from the page itself

As described above, when the viewer is lifted from the page the portionof the page with which the viewer was last in contact remains displayedand interactive. It may also be advantageous for the user to be able to‘freeze’ the current view so that the viewer no longer synchronizes theview with the underlying page. When the user snaps the nearestinteractive or dynamic object to the screen the view is effectivelyfrozen. When the user presses the snap button again, the viewer onceagain synchronizes the view with the underlying page. When there is nointeractive or dynamic object to be snapped, the viewer may stillinterpret the snap as a freeze command, but may do no more than rotatethe current view so that it is oriented the right way up, i.e. so thatthe axes of the screen and of the displayed page are aligned. The snapbutton may therefore be used as a freeze button, but as an alternativelythe viewer may provide a freeze button separate from the snap button.

The viewer may provide a mode wherein the axes of the screen and of thedisplayed page are always kept aligned even though the viewer isotherwise synchronizing the view with the underlying page, i.e. theviewer synchronizes the view according to the position and identity ofthe underlying page, but not according to the rotation of the underlyingpage relative to the viewer. This mode has the advantage that thedisplayed view always looks sensible to the user operating the viewer.It has the further advantage that rotation is never allowed to degradethe quality of the displayed image of the page. If rotation is neverrespected by the viewer, then the viewer is also freed from ever havingto compute a rotated page image. As a compromise, the viewer may respectthe nearest multiple of ninety degrees to its actual rotation relativeto the page.

FIGS. 24 and 25 provide an example of the interaction of the viewer with‘secure’ data requiring authorized access. FIG. 24 shows an examplepersonal identification number (PIN) advice letter 230 from a bank. Boththe account number 232 and PIN 234 are suppressed on the printed page,i.e. printed as a series of X's. FIG. 14 shows the view the viewerprovides of the PIN advice letter. The view shows the actual accountnumber 236 and PIN 238, on the basis that the netpage system hasverified that the user of the viewer is the owner of the data. Theadvice letter is recorded on a netpage registration server as beingowned by a particular user, i.e. by the user to whom the letter wasoriginally addressed. The viewer is recorded as owned by the same user.The identity of the actual user is optionally verified with respect tothe identity of the owner of the viewer by verifying the fingerprint ofthe actual viewer against the fingerprint of the owner. The fingerprint,or some other biometric, is recorded by the registration server for theowner. The viewer may incorporate a fingerprint sensor 189 for thepurposes of fingerprint capture. Providing a biometric such as afingerprint or signature to the viewer may place the viewer in a‘secure’ mode wherein secure information is accessible for a period oftime. An indicator, such as a lit LED, may indicate this mode to theuser. Alternatively, secure access is only granted while the user'sbiometric is being sensed. In the example, the actual account number andPIN is then only shown while the user's finger is in contact with thefingerprint sensor.

FIGS. 26 and 27 provide an example of the interaction of the viewer witha fill-in form 240. The form has a number of fill-in fields 242. FIG. 26shows an example form. FIG. 27 shows the view the viewer provides of theform. The stylus 244 can be used to fill in the fields of the form viathe touch-screen. The example shows the form 240 being filled in byhand, pending handwriting recognition according to normal netpagemechanisms.

Netpage input, in the form of digital ink, is labeled to indicate how itwas captured, i.e. through a netpage pen interacting with a printednetpage, or through a stylus interacting with the touch-sensitive screenof a viewer. The digital ink is also labeled with any change in theauthorization state of the viewer, e.g. with respect to the presence ofthe user's finger on the viewer's fingerprint sensor. This allows thepage server, when interpreting netpage input in relation to thecorresponding page description, to ignore document elements not visibleto the user when the input was captured.

Digital ink generated through a viewer is otherwise suitably transformedto look like it came from a netpage pen interacting with the underlyingpage, i.e. the digital ink is labeled with the page ID of the underlyingpage, and the coordinates of position samples in the digital ink aretransformed from the coordinate system of the viewer into the coordinatesystem of the underlying page, according to the view transform currentwhen the position sample was captured. As an alternative, the viewer mayprovide an insertion point specifiable via the stylus, an associatedtext cursor, and text entry via an on-screen keyboard or viacharacter-wise character entry and recognition, in the manner of currentpersonal digital assistants (PDAs).

The viewer may alternatively or additionally contain a mobile telephonetransceiver for longer-range communication with a netpage server via amobile telephone network. If the transceiver supports a third-generation‘always-on’ packet-switched connection, then the viewer may download orstream page content at will. If the transceiver only supports acircuit-switched connection, then the viewer may choose to connect anddownload a full page description whenever it encounters a new page,provide local navigation of the page via the downloaded pagedescription, and only make further connections when dynamic contentneeds to be displayed or when hyperlinks are activated.

If the viewer incorporates a longer-range transceiver, then it may actas a netpage base station for wireless netpage pens and other netpagesensing devices.

When used to interrogate secure data, the viewer may incorporate afingerprint sensor, such as the Vericom FPS200, to allow it tocontinuously monitor and verify the identity of the user. The processortypically interrogates the fingerprint sensor via a serial interface.

The viewer may incorporate several levels of power management. After aperiod of inactivity the viewer may inactivate the display. After alonger period of inactivity the processor may enter a power-conservingquiescent state. Power management may be coupled with the image sensorand/or the touch sensor, allowing wake-up on screen interaction ormovement. The viewer may also incorporate an accelerometer for thispurpose.

The viewer may be configured with software allowing it to function as apersonal digital assistant (PDA). The components and functions of theviewer may also be incorporated into a mobile phone.

The viewer handles a variety of page content, including styled text,outline graphics, bitmapped images, audio, and video. While audio andvideo are by their nature dynamic (i.e. time-varying), text, graphicsand images are normally static. They may, however, be part of a dynamicstream representing the output of an interactive application, executingremotely or within the viewer. A local application may be defined by ascript object which is interpreted by the viewer, e.g. coded in Java orsimilar.

Page content falls into three categories: (1) static elements whichappear on the printed page; (2) static elements which only appearthrough the viewer; and (3) dynamic elements which only appear throughthe viewer. The first category includes all the visual elements of thepage. The second category includes, for example, elements associatedwith controls for dynamic content, e.g. playback controls for a videoclip, and elements associated with secure information. The thirdcategory includes anything of a dynamic nature, e.g. a video clip. Adynamic element may have a static counterpart in the page description sothat it has a meaningful visual appearance on the printed page. A videoclip, for example, may be represented by a rectangle of the appropriatesize showing the title of the clip.

Document elements in the second and third categories have associatedview filters which restrict their appearance. The ‘viewer view’ filterrestricts the element to appearing through a viewer. The ‘secure view’filter restricts the element to appearing through an authorized viewer.The view filter class diagram is shown in FIG. 29.

A digital ink stream is generated with a maximum data rate of about 5Kbit/s [13]. The viewer generates a view transform stream with a similarmaximum data rate. The viewer therefore generates wirelesscommunications traffic to the base station with a maximum data rate ofabout 10 Kbit/s, which is negligible.

To minimize wireless communications traffic from the base station to theviewer, it may be mandated that only one dynamic object can be active ata time. Even though more than one object may be visible through theviewer, the page server may deactivate all but one such object. It may,for example, only leave the dynamic object closest to the center of theviewer's display active. The user may be able to explicitly activate analternative dynamic object by clicking on it with the stylus, or theuser may be required to explicitly activate any dynamic object, thusimplicitly deactivating any currently active object.

Where a dynamic object represents an application window, the page servertypically relays to the application any changes to the viewer's viewtransform which relate to the application window. This allows theapplication to generate output when the window is visible, and to tailorthe output to the actual overlap between the window and the viewer'sview. The output from the application may be in the form of a videostream, or it may be in the form of a stream of graphics commandsoperating on text, graphics and images.

It is possible to display output from a remote application through theviewer, and capture stylus input through the viewer and route it to theremote application, without the application having to be explicitlydesigned for interaction with the viewer. Applications typicallyinteract with user interface devices such as bitmapped displays,keyboards and pointing devices in a device-independent manner byutilizing the services of a windowing system, and this allows the userinterface devices to be remote from the applications without changinghow the applications interact with them.

As an alternative to rendering the view on demand, the viewer may renderthe entire page into a memory buffer and then simply display a suitablytransformed window into the buffer. However, since the rotation ofrelatively low-resolution text produces unacceptable text quality, thepage must either be rendered at a higher resolution than the displayresolution and appropriately lowpass filtered before display, or thedisplay resolution must be higher than assumed so far.

As a further alternative, the viewer may rely on the page server or thebase station to render the page and supply it to the viewer, typicallyin compressed form. In this case the viewer is still responsible forintegrating dynamic streams with the static page view.

As yet another alternative, the viewer may rely on the page server orthe base station to render the current view and supply it to the viewer,typically in compressed form. In this case the viewer need contain nosupport whatsoever for interpreting and rendering the variety ofelements which may comprise a page description. Assuming a 320×240 RGBpixel display, a 10 Hz update rate, and 10:1 compression, this requiresa data rate of about 1.8 Mbit/s, which is within the realms ofpracticality using currently-available personal-area, local-area andwide-area wireless networking technologies as discussed above.

FIG. 30 illustrates the interaction between the netpage viewer and thenetpage network. The viewer's time-varying view transform, as well asdigital ink captured via the viewer, are transmitted (at A) to a netpagebase station. The base station relays (at B) the view transform anddigital ink to the page server which holds the electronic description ofthe physical page with which the viewer is interacting, as identified bythe page ID embedded in the tags of the page. The page server interpretsthe view transform and digital ink with respect to the page, andinitially responds (at C) with the page description. It subsequentlytransmits (at C) dynamic object updates and streaming dynamic content.The base station relays (at D) data from the page server to the viewer.

The page server may notify (at E) an application that the viewer's viewonto a window associated with the application has changed, and theapplication may respond (at F) with commands instructing the viewer toupdate parts of its current view. The page server relays (at C) thesecommands to the base station, which relays (at D) the commands on to theviewer.

Handwritten text can be transferred to the underlying page before orafter it is recognized by the netpage system and converted to computertext. If transferred after conversion, the viewer can transfer thecomputer text to the underlying page in place of the handwritten text.Similarly, a signature can be transferred to the page before or after itis used by the netpage system to verify the identify of the user. Iftransferred after verification, the viewer can transfer a verificationicon and/or a serial number in place of the signature.

Whilst the display of the preferred embodiment is visual, a Brailleviewer may be made according to the invention. A Braille viewer isanalogous to the optical viewer. It displays in registered fashion andvia a tactile Braille display the text of a netpage. It also displaystext labels corresponding to graphics and images, where available in thepage description. Because Braille characters are typically rendered atlarger sizes than visually-recognized characters, the Braille viewertypically presents a zoomed view of the underlying page. This means thatas the viewer is moved over the page, the display moves correspondinglyfaster.

In other embodiments the viewer can be transparent when it is not incontact with a page, so that while it is being placed on a page, thepage is seen through the viewer. This can be implemented using a LCDshutter which is reflective when opaque, positioned behind atransmissive color display. However, the netpage viewer design issimplified if the viewer is always opaque, and only ever virtuallytransparent.

Whilst the invention has been described with reference to the netpagesystem which uses invisible tags, the invention is not limited to thenetpage system or the use of invisible tags. If desired, the inventionmay utilize tags or codes which are visible to the average unaided humaneye, such as bar codes. The tags need not merely encode an identitywhich is then used to look up the relevant files. The tags may encodeinstructions at a higher level. For example a tag may encode aninstruction of “play chapter 99”. If invisible tags are used they neednot be limited to the tags disclosed in relation to the netpage system.Other tagging systems are available and any suitable tagging system maybe used. The invention is not limited to the use of inks which absorbcertain wavelengths or fluoresce certain wavelengths. Magnetic inks,surface modification, including apertures, modification of the structureof the substrate itself all fall within the scope of the invention. Thesystems and methods to link the viewer of the present invention and thesource of the document data are not limited to netpage systems. A viewermay be linked by a cable to a single computer, rather than a network ofcomputers.

The present invention has been described with reference to a preferredembodiment and number of specific alternative embodiments. However, itwill be appreciated by those skilled in the relevant fields that anumber of other embodiments, differing from those specificallydescribed, will also fall within the spirit and scope of the presentinvention. Accordingly, it will be understood that the invention is notintended to be limited to the specific embodiments described in thepresent specification, including documents incorporated bycross-reference as appropriate. The scope of the invention is onlylimited by the attached claims.

1. A viewing device for use with coded data on a surface, said devicecomprising: a sensor arrangement for sensing the coded data when thedevice is placed on the surface, said sensor arrangement having anoptical sensor including an infrared LED and an image sensor; aprocessor in signal communication with the sensor arrangement, saidprocessor configured to decode the coded data; a transceiver fortransmitting the decoded data to a computer system, and to subsequentlyreceive a file pre-associated with the decoded data from the computersystem; and a display configured to display the received file to a user,wherein the processor is configured to strobe the LED in synchrony withan image capture of the image sensor to prevent motion-blurring ofcaptured images.
 2. The viewing device of claim 1, wherein the opticalsensor includes a lens and a beam splitter/combiner to allow lightreflected from and to the LED and the image sensor to follow the samepath.
 3. The viewing device of claim 1, wherein the image sensorincludes a 200×200 pixel CCD or CMOS image sensor with a near-infraredbandpass filter.
 4. The viewing device of claim 1, wherein thetransceiver supports any wireless transmission standard selected fromthe group consisting of: Bluetooth/IEEE 802.15, IEEE 802.11,HomeRF/SWAP, HIPERLAN, and OpenAir.